CHICAGO — Illinois presented a plan to fix a host of problems at six state juvenile detention centers, among them proposals to increase time in the classroom and ban solitary confinement as discipline, after the state was sued a year and a half ago for poor treatment of incarcerated youths.

The plan, submitted jointly by the Department of Juvenile Justice and the American Civil Liberties Union in Northern District Court, addresses a slew of problems outlined by a panel of experts in September after a lengthy investigation into conditions at the facilities. It’s part of the settlement of a lawsuit filed by ACLU in 2012.

Some of the measures requiring new spending face an uncertain future because of the state’s budget problems. Illinois faces an estimated $1.5 billion loss in revenue due to the scheduled expiration of the state’s temporary tax increase in January 2015.

Youths would be required to have a five-hour school day, with student-teacher ratios of no higher than 10:1 in classes, under the plan. The panel of experts found in September that students were often doing institutional work instead of studying, in part because of a number of teaching and support-staff vacancies.

“There are two ways the state of Illinois can meet the youth to staff ratios in the plan,” Adam Schwartz, senior legal counsel for the ACLU said. “One can be to reduce the number of youths who are locked up in these places. The other would be to increase the number of staff. By far the less expensive solution ... would be to lock fewer of these youths up.”

Department of Juvenile Justice spokeswoman Alka Nayyar said the agency was “pleased to reach an agreement without further litigation and be moving forward.”

The panel’s September report had described incarcerated teens mowing lawns during the school day, being improperly medicated and routinely subjected to more solitary confinement than necessary at the Kewanee, St. Charles, Warrenville, Chicago, Harrisburg and Pere Marquette. It also found youths being kept at detention facilities after release dates because state officials could not find them outside housing.

The remedial plan filed with the courts on Friday would require incarcerated youths to spend eight hours per day, not counting time spent showering or at meals, outside of their rooms.

To address a void in mental health services identified by the experts, the department would be required to hire a child and teen psychologist to oversee services for all six facilities, and increase both mental health and security staffing levels at the detention centers.

The plan bans the use of solitary confinement for disciplinary reasons, after the report from experts said youths were sometimes placed in solitary confinement for as much as 22 hours a day.

Page 2 of 2 - It also would require staff to be trained to better protect gay, lesbian and transgender youths from violence and harassment, and mandates case-by-case decisions for where to house transgender youth and for whether to begin hormone treatment therapy for them.

If Judge Matthew Kennelly approves the remedial plan in the coming weeks, its rollout would be monitored and enforced by court-appointed experts over coming months. Kennelly is expected to give guidance about how he wants to proceed with the plan at a status hearing in Chicago next week.